Questions regarding efficient storing and representing data within a software application.

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0
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0answers
12 views

How can I avoid duplicating information in this scenario?

I have a Data class that can be placed inside a DataCollection class that can be placed inside a DataCollectionCollection class. Kinda like an egg can placed inside a box that can be placed inside a ...
2
votes
0answers
29 views

Cache-conscious data structure that does not require hashing

I am looking for a cache conscious data structure that does not require hashing. This is to avoid HashDoS without needing to use cryptographic PRFs such as SipHash, which are slow (~1 cycle/byte) ...
4
votes
2answers
75 views

Database design, processor vs inconsistency

I was wondering, if I have a table that stores, lets say, a user's transactions, then when I need to fetch the user's current balance I would have to go and use SUM() like SELECT SUM(value) FROM ...
1
vote
1answer
110 views

Does algorithm time complexity O(5) considered as O(1)? [duplicate]

I have someone homework to make and in the instructions it says that we need to implement a function in O(1). Now, does it mean that I can make my function in O(5) or O(2) or whatever?
3
votes
1answer
194 views

How to pass data to OOP objects?

I'm new to this whole thing, so please tell me if I'm doing this wrong of if there's a better spot for my question. I'm making a game with basic systems for projectiles, npcs and items. This game ...
0
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2answers
76 views

JSON or XML or other - most time efficient for largely “read” of structured data

Considering that using a relational DB or other hierarchical or such databases is not an option, looking for the alternative approach using a simple (but very fast, efficient, distributed KV-store). ...
7
votes
2answers
124 views

How to best design a job queue with constraints?

Consider the following situation: You have a program which creates numerous 'jobs' that need to be processed and places them into a queue. You have other worker programs which grab the next 'job' in ...
4
votes
1answer
123 views

Word ladder efficency problem

I have a problem dealing with word ladders. The problem is: given two words and a dictionary file, find the shortest word ladder between the two words. So if given the words cat and pot: cat -> ...
4
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0answers
63 views

Modelling a complex schedule of work

I've got a real-world problem that I'm trying to represent and automate. I've simplified and abstracted it down to the following: There are n places of work (P1, P2, ..., Pn). Each place, Pn has a ...
4
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2answers
150 views

How to design an iterable but immutable (read-only) collection

My program models a sport tournament which has one or many events or categories. The class Event has members like players or courts as a List, as well as some dictionaries using the class Map. So far ...
2
votes
2answers
197 views

Is it a bad practice to use JSON strings as keys of objects?

On languages such as Haskell, most datatypes have instances which allow their values to be used as keys of structures such as Maps. JavaScript has reasonably fast maps, there called objects, but those ...
-5
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0answers
22 views

I have 3 groups of constant values where I need to return the group name if my search element matches with any of the element in group

I have 3 groups like: days = {Sat, Sun, Mon}; weeks = {1, 2, 3, 4}; months = {Aug, Sep, Dec}; I have an element Sun, if this element matches with any of group, in this case it is Sunday, so return ...
2
votes
1answer
65 views

Caching in '3D' - data-structures and octree recursion - hrrm!

The Situation: I have 68GB of data that is conceptually realized as a 3D matrix of 8-bit values with dimension 4096*4096*4096. I need to access multiple sections of this data for processing in a ...
1
vote
1answer
64 views

Joining binary trees

Suppose we have a set of binary trees with their inorder and preorder traversals given and where no tree is a subtree of another tree in the given set. Now another binary tree Q is given. Find ...
1
vote
2answers
206 views

What is the best data structure to store 2 keys and 3 values?

Well, I am having two keys and 3 values for that. Say key1,key2,value1,value2,value3. In future may the values can be increased like value4, value5 so on. I need to get the ...
0
votes
1answer
62 views

Datagrids vs Databases - what are the differences?

There are some datagrids I had quick look into: Angular UI Grid ag-Grid, one more link Kendo UI Grid Also, previously I had a very small experience with MySQL. What are the differences between ...
2
votes
2answers
71 views

Algorithm for implementing QOS in my proxy

Here's the situation: I'm making a proxy (for the moment running on my laptop) which deals with HTTP(S) requests from incoming clients (for the moment only one client, i.e. my Chrome browser on my ...
0
votes
1answer
17 views

What relationship describes two different abstractions of the same dataset

I am wondering if there is a specific term for when multiple representations are data equivalent. Meaning that you can transfer the data from one representation to the other without any loss of data. ...
-1
votes
1answer
71 views

Data structure for storing sorted data

What's a good way to store loads of sorted string on a file so that inserts and reads are fast? I could store it up in a tree, and read/modify/store it as needed, but that seems wasteful for ...
2
votes
1answer
52 views

Matrix multiplication range queries

I have a huge list of matrix i.e A = {M0, M1, M2 .. Mn}. I have a task to find the product of all the matrices in a given range {x,y} i.e Mx * Mx+1 * Mx+2 ... * My. I would like to know if there is ...
1
vote
2answers
65 views

What design patterns exist for large dataset manipulation within MVC for a rich client data grid?

I want to feed an HTML5 data grid with large data sets that the client will want to manipulate in different ways, e.g. aggregation, grouping, pivoting. The data comes from different web services and ...
0
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0answers
14 views

PHP array implementation what hashtable's 'bool persistent' does stand for? [migrated]

I read So let’s just say that persistent specifies that the hash table can live between multiple requests. In Nikic's blog about PHP array implementation There is no further information in ...
-2
votes
4answers
59 views

How can I represent a multi-dimensional grid? [closed]

I'm trying to find an efficient way to represent a grid in any number of dimensions. I would want to be able to specify a set of coordinates and then get the value stored in the location on the grid. ...
5
votes
1answer
85 views

How does cuckoo hashing guarantee O(1) lookups in presence of persistent hash collisions

Most hash table implementations guarantee O(1) average case but O(n) maximum case for lookup (where 'n' is the number of keys in the table). But Cuckoo Hashing is described as O(1) maximum. ...
-3
votes
2answers
58 views

class name for linked lists

I have a question about how to name a class in java. Could a class name be arbitrary or have to obey some rules? For example, I want to define linked lists in a class, does the class name have to be ...
1
vote
1answer
29 views

File structure for storing pixels that changed from one image to another

Have two images with the same dimensions. I want to create a file that contains information on what pixels are different between the two images. The file should also tell me the value of the new ...
1
vote
0answers
80 views

How to structure enum data to achieve the desired effect

I'm making a framework for building simple html websites for an embedded system and I want to make it bulletproof in a way that a user can't make mistakes in building the html document. As I've ...
4
votes
2answers
163 views

Can StringBuilder be used to effectively store and manage multiple variables of data?

Using C# I want to create one or more text files to store all the data pertaining to a particular 'Thing' on the same line. I am presently leaning towards StringBuilder as per the following. ...
1
vote
1answer
58 views

How many vertices/nodes are too many in a graph and stop being beneficial?

Background I'm working on a project that requires me to keep track of transactions as well as the flow of items in a game. In order to do that, I'm storing those transaction in a graph db ...
2
votes
2answers
154 views

C++ object references vs. lookup

Let's assume there are 2 classes: Country and City. Both of them have names, so a map would suit as conainer map<std::string, Country> countries; In the country class there is a similar map ...
2
votes
1answer
95 views

What method for storing a text file in memory (c not c++) would allow me to open any format(UTF-8, Binary, etc) and a file of any size?

My first thought here is to use a dynamic array, but I am looking for something better. Currently I have the text files open into "chunks". Every word or group of spaces makes up a "chunk". Then I ...
1
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0answers
23 views

Pagination with multiple groupings

I have a data model that looks like this: Group 1 --Sub group1 ----item1 ----item2 ----item3 --Sub group2 ----item1 ----item2 ----item3 Group 2 --Sub group1 ----item1 ----item2 ----item3 --Sub ...
3
votes
1answer
91 views

PHP OOP, structuring my objects properly

I have an architecture similar to this: User (Name, Email, ID...) ---- Studios (Name, Location, Description...) ---------- Videos (Title, Description, URL, Length, Views...) Simply put, a user can ...
0
votes
2answers
50 views

How to model a property with two different formats and ranges

I am designing a JSON based data schema to describe the visual appearance of blocks similar to HTML elements. It should feel familiar for somebody knowledgable in HTML/CSS but is more restrictive due ...
3
votes
1answer
335 views

What do banks actually use as a data type for money? [closed]

I'm aware of a few good options: Big integers (e.g., int64_t, mpz_t, any bignum lib) to represent cents or 10-n cents—say, an integer represents 1/100 of a penny ($1.05 == 10500). This is called a ...
0
votes
1answer
84 views

Data Structure for Form or Survey [closed]

I am planning an app which allows users to complete surveys/forms. I'm having trouble planning the data schema for the forms. I really want to have a data structure which can be mostly automatically ...
3
votes
2answers
212 views

Can a tree be used to create a stack?

I'm aware that linked lists, sets and arrays can be used to create stacks by themselves. The theory behind it is this linked-list: In some languages, a linked-list is substitutable for an array. ...
-2
votes
1answer
49 views

Considerations when making data structure and algorithm choices [closed]

What are some reasons you may choose a worse runtime algorithm? And what are some advantages of a linked list vs a hash table/array where access is constant time.
2
votes
1answer
144 views

Standard System that connects to any datasource without much/any source-specific code?

We are a small team doing work on a LoB system that needs to connect to varied systems such as ERPs and CRMs to extract business processes like invoices, customer info, production orders and the such, ...
1
vote
2answers
53 views

DB Design for non static front-end

I have a question about best practices to design a database which have to hold the following data: There is a page with a questionnaire which has default questions like Firstname, Lastname, Street... ...
5
votes
1answer
150 views

Is it possible to have these characteristics in a data structure?

I was tutoring a student that came up with this assignment. It basically requires a data structure with the following characteristics: it holds a set of integers in {1, 2, ..., n} n is power of 2 ...
7
votes
2answers
318 views

Is using this complex data structure bad practice?

Right now in my current company I must "parse" a csv and extract some data out of it (in the sense of data mining). I surprised myself by defining the following data structure (Java 8): static ...
6
votes
6answers
255 views

Should I always store parsed data in database before manipulating?

I am about to start a new project which involves taking an excel file, parsing the data (php-excel-reader) and then using the parsed values in a HTML email. My question is pretty simple. Is it better ...
10
votes
4answers
287 views

Is there a standard way or standard alternative to packing a struct in c?

When programming in C I have found it invaluable to pack structs using GCCs __attribute__((__packed__)) attribute so I can easily convert a structured chunk of volatile memory to an array of bytes to ...
2
votes
1answer
134 views

Suggestions for structuring complex json structures?

I can't find many tips for how to design complex json structures beyond the obvious tips of not trying to nest too deeply, using defined data types, etc. For example, if I have a location that needs ...
3
votes
3answers
88 views

Is it odd if Nodes in a LinkedList held references to the List object?

Its like, I want to call .moveToBefore(Node) on a Node object and have the node relocate to before the node passed in. The problem arises if the node passed in is the head node. The List object will ...
5
votes
3answers
142 views

How to create “constructors” for structures in C

The problem I have this structure that I want to create a "constructor" for it. struct example { int x, y, z; /* various members */ struct another *another; /* pointer to another structure ...
0
votes
0answers
19 views

Joins between datasets in data models

I'm struggling to understand how to join data between data domains in application properly. Say, I have three domains, User, Post and Like: User - id - login - password - active - ... Post - id - ...
0
votes
0answers
41 views

Bounded Priority queue with constant time amortized delete min and insert

Given a bounded priority queue (with keys between 1 and k), is there any data structure with amortized constant time for delete min and insert and find min, where the worst case time for these ...
-2
votes
1answer
74 views

Should I be using XML to store configuration values in a database?

There are a couple of answers on SE comparing single-row table vs. name-value-pair table used for config settings, but I haven't seen anyone arguing for using XML (or JSON) as a name-value pair ...